The present invention relates generally to a device for admixing liquid and gaseous phases, and more particularly to a device for mixing a gaseous phase into a liquid phase which is particularly suitable for aerobic microbiological processes and the like.
Devices of the type in question are already known. They have vessels which accommodate the liquid phase, and it is known to provide a tubular guide baffle in such a vessel, forming the guide baffle with apertures in its circumference, and providing adjacent one end of the guide baffle an impeller which draws the liquid phase through the openings and into the guide baffle from the space surrounding the same. The gaseous phase is admitted into the vessel, and as it is drawn through the openings into the guide baffle together with the liquid phase, the two become mixed.
There are circumstances in which the vessel of such an apparatus must be tall and substantially cylindrical but can have only a relatively small diameter. One of these is the fact that frequently space is at a premium and larger-diameter vessels cannot be accommodated. If such a relatively high vessel is used, then the hydrostatic pressure of the liquid phase in the filled vessel is considerable in the lower region thereof, due to the column of liquid located in the upper regions. This pressure can be so great that the gaseous phase must be forcibly pressed into the interior of the vessel by means of compressors. If the vessel is large, and therefore requires substantial quantities of the gaseous phase, such installations are very expensive both as to their construction and operation, and therefore quite frequently cannot be operated economically.